Multidimensional virtual globe for geo big data visualization

In this paper, we presented a web application created using the NASA WebWorldWind framework. The application is capable of visualizing n-dimensional data using a Voxel model. In this case study, we handled social media data and Call Detailed Records (CDR) of telecommunication networks. These were retrieved from the "BigData Challenge 2015" of Telecom Italia. We focused on the visualization process for a suitable way to show this geo-data in a 3D environment, incorporating more than three dimensions. This engenders an interactive way to browse the data in their real context and understand them quickly. Users will be able to handle several varieties of data, import their dataset using a particular data structure, and then mash them up in the WebWorldWind virtual globe. A broad range of public use this tool for diverse purposes is possible, without much experience in the field, thanks to the intuitive user-interface of this web app

NASA WEBWORLDWIND: MULTIDIMENSIONAL VIRTUAL GLOBE FOR GEO BIG DATA VISUALIZATION

In this paper, we presented a web application created using the NASA WebWorldWind framework. The application is capable of visualizing n-dimensional data using a Voxel model. In this case study, we handled social media data and Call Detailed Records (CDR) of telecommunication networks. These were retrieved from the "BigData Challenge 2015" of Telecom Italia. We focused on the visualization process for a suitable way to show this geo-data in a 3D environment, incorporating more than three dimensions. This engenders an interactive way to browse the data in their real context and understand them quickly. Users will be able to handle several varieties of data, import their dataset using a particular data structure, and then mash them up in the WebWorldWind virtual globe. A broad range of public use this tool for diverse purposes is possible, without much experience in the field, thanks to the intuitive user-interface of this web app

Radiosondaggi atmosferici nell’area etnea

RADIOSONDAGGI ATMOSFERICI NELL’AREA ETNE

Monitoring and forecasting Etna volcanic plumes

In this paper we describe the results of a project ongoing at the Istituto Nazionale di Geofisica e Vulcanologia (INGV). The objective is to develop and implement a system for monitoring and forecasting volcanic plumes of Etna. Monitoring is based at present by multispectral infrared measurements from the Spin Enhanced Visible and Infrared Imager on board the Meteosat Second Generation geosynchronous satellite, visual and thermal cameras, and three radar disdrometers able to detect ash dispersal and fallout. Forecasting is performed by using automatic procedures for: i) downloading weather forecast data from meteorological mesoscale models; ii) running models of tephra dispersal, iii) plotting hazard maps of volcanic ash dispersal and deposition for certain scenarios and, iv) publishing the results on a web-site dedicated to the Italian Civil Protection. Simulations are based on eruptive scenarios obtained by analysing field data collected after the end of recent Etna eruptions. Forecasting is, hence, supported by plume observations carried out by the monitoring system. The system was tested on some explosive events occurred during 2006 and 2007 successfully. The potentiality use of monitoring and forecasting Etna volcanic plumes, in a way to prevent threats to aviation from volcanic ash, is finally discussed

A Statistical Approach to Evaluate the Tephra Deposit and Ash Concentration from Puff Model Forecasts

In this paper we present a new statistical approach able to provide tephra deposit load and ash concentration using PUFF, a lagrangian model widely used to forecast volcanic ash dispersal during volcanic crisis. We perform a parametric study in order to analyze the influence of each input parameter on model outputs. For this test, we simulate two eruptive scenarios like to the 2001 (Scenario 1) and 1998 (Scenario 2) Etna eruptions using high resolution weather data and a domain of 170 x 170 km. Results show that for both scenarios, we are able to calculate the tephra deposit load and ash concentration but the use of millions of particles is required. Specifically, up to 33 and 220 millions of particles were necessary to accurately predict the tephra deposit and ash concentration in air, respectively. This is approximately two orders of magnitude larger than values typically considered running PUFF. The parametric study shows that the horizontal diffusion coefficient, the time step of the simulations, the topography and the standard deviation of the particle distribution greatly affect the model outputs. We also validate the model by best fit procedures. Results show a good comparison between field data of the 2001 Etna eruption and PUFF simulations, being inside 5 and 1/5 times the observed data, comparable with results of Eulerian models. This work will allow to reliably outlining the areas of contaminated airspace using PUFF or any other lagrangian model in order to define the No Fly Zone and ensure the safety to aviation operations as required after the Eyjafjallajökull eruption

Hotspot Analysis: an experimental Python plugin to enable LISA mapping into QGIS

The possibility of linking maps with statistical processes represents one of the meaningful advantages characterizing the latest generation of GIS software. In the last decades, manifold statistical techniques have been adapted as well as designed to enable geographic data analysis. Among these techniques, particularly popular - and widely adopted in many research fields - is the spatial autocorrelation analysis using LISA (Local Indicators for Spatial Association). LISA statistics are currently implemented into different programming libraries (e.g R- spdep https://cran.r-project.org/web/packages/spdep, Python-PySAL http://pysal.github.io, etc.), into Free and Open Source spatial statistical Software (eg. GeoDA http://geodacenter.github.io) as well as into proprietary GIS software suites. Within the most famous FOSS GIS, the access to LISA mapping capabilities is currently enabled only through command line while dedicated plugins have not been formally made available yet. We present here the Hotspot Analysis plugin, an experimental QGIS Python plugin aimed both to facilitate the access to to LISA mapping tools for users with no advanced programming skills – exploiting the user-friendly QGIS environment - as well as to contribute to the growth of the mapping capabilities of this FOSS GIS software. The Hotspot Analysis plugin is based mainly on the Exploratory Spatial Data Analysis (ESDA) module of PySAL and PyQGIS, providing a simplified interface to run LISA tools starting from vector layers. The stable version of plugin is available on the QGIS Python Plugins Repository (https://plugins.qgis.org/plugins/HotspotAnalysis ) while the development version as well as documentation and test data are available on GitHUB (https://github.com/danioxoli/HotSpotAnalysis_Plugin). The main plugin features, including installation requirements and computational procedures, are here described together with an example of the possible applications of the Hotspot analysis

Eruption column height estimation of the 2011-2013 Etna lava fountains

In this paper, we use calibrated images collected by the video-surveillance system of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, to retrieve the height of the eruption column during the recent Etna explosive activity. The analysis is carried out on nineteen lava fountains from the New South East Crater dataset. The novel procedure described in this work is achieved in three main steps: at first we calibrated the camera, then we selected the images which recorded the maximum phase of the eruptive activity, and finally we applied an appropriate correction to account for the plume projection on the camera line of sight due to the wind. The results show that the column altitudes range between 6 and 9 km (upper limit of the camera system). The comparison with the plume height values estimated from the analysis of several SEVIRI and MODIS satellite images, show a good agreement. Finally, for nine events we also evaluated the thickness of the volcanic plumes in the umbrella region which ranges between 2 and 3 km

Eruption column height estimation of the 2011-2013 Etna lava fountains

In this paper, we use calibrated images collected by the video-surveillance system of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, to retrieve the height of the eruption column during the recent Etna explosive activity. The analysis is carried out on nineteen lava fountains from the New South East Crater dataset. The novel procedure described in this work is achieved in three main steps: at first we calibrated the camera, then we selected the images which recorded the maximum phase of the eruptive activity, and finally we applied an appropriate correction to account for the plume projection on the camera line of sight due to the wind. The results show that the column altitudes range between 6 and 9 km (upper limit of the camera system). The comparison with the plume height values estimated from the analysis of several SEVIRI and MODIS satellite images, show a good agreement. Finally, for nine events we also evaluated the thickness of the volcanic plumes in the umbrella region which ranges between 2 and 3 km

A multi-sensor approach for volcanic ash cloud retrieval and eruption characterization: the 23 November 2013 Etna lava fountain

Volcanic activity is observed worldwide with a variety of ground and space-based remote sensing instruments, each with advantages and drawbacks. No single system can give a comprehensive description of eruptive activity, and so, a multi-sensor approach is required. This work integrates infrared and microwave volcanic ash retrievals obtained from the geostationary Meteosat Second Generation (MSG)-Spinning Enhanced Visible and Infrared Imager (SEVIRI), the polar-orbiting Aqua-MODIS and ground-based weather radar. The expected outcomes are improvements in satellite volcanic ash cloud retrieval (altitude, mass, aerosol optical depth and effective radius), the generation of new satellite products (ash concentration and particle number density in the thermal infrared) and better characterization of volcanic eruptions (plume altitude, total ash mass erupted and particle number density from thermal infrared to microwave). This approach is the core of the multi-platform volcanic ash cloud estimation procedure being developed within the European FP7-APhoRISM project. The Mt. Etna (Sicily, Italy) volcano lava fountaining event of 23 November 2013 was considered as a test case. The results of the integration show the presence of two volcanic cloud layers at different altitudes. The improvement of the volcanic ash cloud altitude leads to a mean difference between the SEVIRI ash mass estimations, before and after the integration, of about the 30%. Moreover, the percentage of the airborne “fine” ash retrieved from the satellite is estimated to be about 1%–2% of the total ash emitted during the eruption. Finally, all of the estimated parameters (volcanic ash cloud altitude, thickness and total mass) were also validated with ground-based visible camera measurements, HYSPLIT forward trajectories, Infrared Atmospheric Sounding Interferometer (IASI) satellite data and tephra deposits

Pacing ventricolare destro: una risorsa o una minaccia?

Early after the beginning of the pacemaker era, endocardial right ventricular apex has been the most extensively used site for cardiac pacing because it was easily accessible and reliable in a long-term perspective. However many data have demonstrated that this kind of pacing is suboptimal from a physiologic point of view because it causes several adverse effects such as altered ventricular contraction geometry, mitral regurgitation, perfusion alterations and interference with myocardial ion channels which determine a worsening of left ventricular function. Several strategies have been proposed to solve these problems (alternative pacing sites, specific algorithms able to reduce the percentage of ventricular pacing) which are still under evaluation. In this review we analyzed the effects of right apical ventricular pacing and its possible alternatives